The present invention relates to a digitally programmable signal generator (DPSG) and method. Digitally programmable signal generation is a well known art, the essence of which is the creation of digital and analog signals which are specified by digitally encoded data stored in a primary memory means. The digital data stored in the primary memory means is either converted directly into an output signal or may be multiplexed into secondary (higher speed) memory means and then converted into the output signal. Existing methods for generating digitally programmable signals are constrained to operate at clock rates of less than one gigahertz (1 GHz). The present invention extends the operation of DPSGs into the GHz range, while preserving all of the current art's DPSGs' operational features. The construction of GHz clock rate DPSGs allows for the production of digital and analog signals with nanosecond (ns) and subnanosecond features. The present invention permits the use of lower speed (hence less expensive) components as the primary memory means of the DPSG.
In applications such as Atomic Vapor Laser Isotope Separation (AVLIS) wherein the isotopic ratios of materials are modified via an isotope specific photoionization process, the efficiency of the process is related to the spectral bandwidth of the lasers. The use of GHz bandwidth DPSGs will enable implementation of optimal laser spectral forms. Previous approaches in such AVLIS applications have not been optimal.
In addition to AVLIS processes, DPSGs are currently in use in a wide range of other fields including spectroscopy, telecommunication, computer science, radar, laser-radar, ECM (Electronic countermeasure) systems and test equipment. All of these fields contain applications in which GHz bandwidth DPSGs would be of great value.